Browsing by Subject "Renal calculi"

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    Collagen fibrils and cell nuclei are entrapped within Randall's plaques but not in CaOx matrix overgrowth: A microscopic inquiry into Randall's plaque stone pathogenesis
    (Wiley, 2022) Canela, Victor Hugo; Bledsoe, Sharon B.; Worcester, Elaine M.; Lingeman, James E.; El-Achkar, Tarek M.; Williams, James C., Jr.; Anatomy, Cell Biology and Physiology, School of Medicine
    Calcium oxalate (CaOx) stones can grow attached to the renal papillary calcification known as Randall's plaque. Although stone growth on Randall's plaque is a common phenomenon, this mechanism of stone formation is still poorly understood. The objective of this study was to investigate the microenvironment of mature Randall's plaque, explore its molecular composition and differentiate plaque from CaOx overgrowth using multimodal imaging on demineralized stone sections. Fluorescence imaging showed consistent differences in autofluorescence patterns between Randall's plaque and calcium oxalate overgrowth regions. Second harmonic generation imaging established the presence of collagen only in regions of decalcified Randall's plaque but not in regions of CaOx overgrowth matrix. Surprisingly, in these stone sections we observed cell nuclei with preserved morphology within regions of mature Randall's plaque. These conserved cells had variable expression of vimentin and CD45. The presence of nuclei in mature plaque indicates that mineralization is not necessarily associated with cell death. The markers identified suggest that some of the entrapped cells may be undergoing dedifferentiation or could emanate from a mesenchymal or immune origin. We propose that entrapped cells may play an important role in the growth and maintenance of Randall's plaque. Further characterization of these cells and thorough analyses of the mineralized stone forming renal papilla will be fundamental in understanding the pathogenesis of Randall's plaque and CaOx stone formation.
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    Sample Preparation and Analysis Protocols for the Elucidation of Structure and Chemical Distribution in Kidney Stones
    (Elsevier, 2024) Elagamy, Samar H.; Sommer, Andre J.; Williams, James C., Jr.; Anatomy, Cell Biology and Physiology, School of Medicine
    Examining intact kidney stones both qualitatively and quantitatively can be difficult due to their size and fragility. Many modern analysis methods often lead to the destruction of the stone's structure during sample preparation. Preserving the structural integrity is crucial for accurately determining the chemical distribution of the components of kidney stones, which, in turn, improves our understanding of the disease's etiology. Infrared microspectroscopy and imaging play a vital role in revealing the stone's microstructure and component distribution. Consequently, this research focuses on investigating the impact of different sample preparation techniques on kidney stone analysis using infrared microspectroscopy. Specifically, it explores how polishing the surface of cross-sectioned stones influences the results. The polishing was performed utilizing abrasive discs and lapping films. A polishing device was also designed for the optimization of sample preparation. Additionally, this work involved a comparison of reflection infrared imaging with Attenuated Total Internal Reflection (ATR) infrared microspectroscopic imaging for the analysis of the microstructure of urinary stones.